Gas chromatograph carrier gas pressure control system and method

Abstract

The invention belongs to the technical field of gas chromatographs, and particularly relates to a gas chromatograph carrier gas pressure control system and method.The control system comprises a computer module, a pressure control unit, a power source device and a pressure stabilizing gas source; wherein the voltage stabilizing gas source is used for inputting carrier gas into the gas chromatograph, the power supply device is electrically connected with the pressure controller unit and is used for supplying power to the pressure control unit, and the pressure control unit is electrically connected with the computer module; the control method mainly comprises the step that the computer module is used for conducting PID control on the carrier gas pressure output by the pressure stabilizing gas source through the pressure control unit. According to the invention, the pressure of the carrier gas can be accurately controlled, the performance of the gas chromatograph can be effectively improved, the real-time performance and accuracy of gas analysis are improved, and the maintenance workload of the gas chromatograph is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of gas chromatographs, and in particular relates to a gas chromatograph carrier gas pressure control system and method. Background Art

[0002] As an important gas analysis tool, gas chromatograph is widely used in industries such as petroleum, chemical industry, coal mining, food and drug inspection, and environmental monitoring. The high efficiency, high selectivity, high sensitivity, and high reliability of gas chromatograph provide an excellent solution for gas component analysis in complex multi-component situations, and can effectively solve problems such as process control, environmental safety, and emergency rescue in industrial production product distribution.

[0003] When in use, a gas source is needed to provide the gas chromatograph with a carrier gas such as hydrogen or helium, which serves as the mobile phase of the chromatographic column to carry the sample into the chromatographic column for separation. The pressure of the carrier gas is a key parameter and needs to be maintained within a specific range. Excessive pressure will damage the chromatographic column, while too low pressure will result in incomplete separation, affecting the analysis results.

[0004] However, currently, gas cylinders are commonly used as carrier gas sources, and pressure gauges are used to detect the pressure of the output carrier gas. The carrier gas pressure is monitored by staff, and the pressure of the carrier gas cannot be accurately controlled, which affects the accuracy and precision of the gas chromatograph analysis data to a certain extent. Summary of the invention

[0005] Based on the above problems, the purpose of the present invention is to provide a stable and reliable gas chromatograph carrier gas pressure control system and method, so as to realize the precise control of the gas chromatograph carrier gas pressure by remote control on the computer side, thereby improving the performance of the gas chromatograph and the real-time and accuracy of the analysis, and reducing the maintenance workload of the gas analysis system.

[0006] The technical solution adopted by the present invention is: a gas chromatograph carrier gas pressure control system, comprising: a computer module, a pressure control unit, a power supply device and a pressure-stabilized gas source;

[0007] The stabilized pressure gas source is used to store and output the carrier gas, and input the carrier gas into the gas chromatograph through the pressure control unit;

[0008] The pressure control unit is electrically connected to the computer module, and controls and adjusts the pressure of the carrier gas input into the gas chromatograph through the computer module and the pressure control unit;

[0009] The power supply device is electrically connected to the pressure control unit and is used to supply power to the pressure control unit;

[0010] Further, the pressure control unit includes: a proportional solenoid valve, a pressure sensor, an integrated power drive circuit module, an electronic amplification and reference circuit module, a digital-to-analog conversion module, an analog-to-digital conversion module, a single-chip control module, and a microprocessor;

[0011] The air inlet of the proportional solenoid valve is connected to a pressure-stabilized air source, and a pressure sensor is provided on the air outlet of the proportional solenoid valve;

[0012] The output signal of the pressure sensor is electrically connected to the single-chip control module through the electronic amplification and reference circuit module and the analog-to-digital conversion module;

[0013] The control end of the proportional solenoid valve is electrically connected to the single-chip control module through an integrated power drive circuit module and a digital-to-analog conversion module;

[0014] The single chip control module is electrically connected to the microprocessor;

[0015] The microprocessor is electrically connected to the computer module.

[0016] In addition, the present invention also provides a gas chromatograph carrier gas pressure control method using the above control system, comprising the following steps:

[0017] First, a carrier gas pressure setting value is input into the computer module and sent to the single-chip microcomputer control system through the microprocessor;

[0018] Then, the pressure sensor is used to collect the sampling signal of the carrier gas pressure value discharged from the pressure-stabilized gas source through the gas outlet of the proportional solenoid valve through the electronic amplification and reference circuit module, and then the analog signal is converted into a digital signal through the analog-to-digital conversion module and sent to the single-chip control module;

[0019] Finally, the actual sampling value of the carrier gas pressure is compared with the input carrier gas pressure set value through the single-chip microcomputer control module to perform PID control, and the control voltage signal is sent to the digital-to-analog conversion module for digital-to-analog conversion. The converted analog signal is used to adjust the opening of the proportional solenoid valve outlet through the integrated power drive circuit module, thereby maintaining the carrier gas output by the stabilized pressure gas source having a stable pressure output value.

[0020] The beneficial effects of the present invention are:

[0021] Based on the carrier gas system of the traditional gas chromatograph, the present invention proposes a stable and reliable gas chromatograph carrier gas pressure control system and method, which is particularly suitable for some explosion-hazardous places. In addition, the precise control of the gas chromatograph pressure can be realized by remote control on the computer side, which can effectively improve the performance of the gas chromatograph, improve the real-time and accuracy of gas analysis, and reduce the maintenance workload of the gas analysis system. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic structural diagram of a gas chromatograph carrier gas pressure control system of the present invention;

[0023] Among them: 1. Computer module; 2. Pressure control unit; 201. Proportional solenoid valve; 202. Pressure sensor; 203. Integrated power drive circuit module; 204. Electronic amplification and reference circuit module; 205. Digital-to-analog conversion module; 206. Analog-to-digital conversion module; 207. Single-chip control module; 208. Microprocessor; 3. Power supply device; 4. Regulated pressure gas source. DETAILED DESCRIPTION

[0024] To make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0025] like Figure 1 As shown, the present invention provides a gas chromatograph carrier gas pressure control system, comprising: a computer module 1, a pressure control unit 2, a power supply device 3 and a pressure-stabilized gas source 4;

[0026] The stabilized pressure gas source 4 is used to store and output the carrier gas, such as a gas cylinder storing hydrogen or helium, which is connected to the gas chromatograph through the pressure control unit 2 to input the carrier gas into the gas chromatograph;

[0027] The pressure control unit 2 is electrically connected to the computer module 1, and the pressure of the carrier gas input into the gas chromatograph is controlled and adjusted through the computer module 1 and the pressure control unit 2;

[0028] The power supply device 3 is electrically connected to the pressure control unit 2 and is used to supply power to the pressure control unit 2;

[0029] Further, the pressure control unit 2 includes: a proportional solenoid valve 201, a pressure sensor 202, an integrated power drive circuit module 203, an electronic amplification and reference circuit module 204, a digital-to-analog conversion module 205, an analog-to-digital conversion module 206, a single-chip control module 207, and a microprocessor 208;

[0030] The air inlet of the proportional solenoid valve 201 is connected to the pressure-stabilizing air source 4, and the air outlet of the proportional solenoid valve 201 is provided with a pressure sensor 202;

[0031] The output signal of the pressure sensor 202 is electrically connected to the single chip control module 207 through the electronic amplification and reference circuit module 204 and the analog-to-digital conversion module 206;

[0032] The control end of the proportional solenoid valve 201 is electrically connected to the single chip control module 207 through the integrated power drive circuit module 203 and the digital-to-analog conversion module 205;

[0033] The single chip control module 207 is electrically connected to the microprocessor 208;

[0034] The microprocessor 208 is electrically connected to the computer module 1;

[0035] Specifically, in this embodiment, the computer module 1 sends an action command to the single-chip control module 207 via the microprocessor 208. The single-chip control module 207 compares the pressure value returned to the single-chip control module 207 by the pressure sensor 202 after data calculation. According to the comparison result, the opening of the proportional solenoid valve 201 is adjusted through the integrated power drive circuit module 203 to realize the overall closed-loop control, thereby ensuring that the carrier gas at the outlet of the proportional solenoid valve 201 has a stable pressure value.

[0036] In addition, the present invention also provides a pressure control method applicable to an intrinsically safe gas chromatograph, comprising the following steps:

[0037] First, a carrier gas pressure setting value is input into the computer module 1 and sent to the single chip control module 207 through the microprocessor 208;

[0038] Then, the pressure sensor 202 is used to collect the sampling signal of the carrier gas pressure value discharged from the pressure-stabilized gas source 4 through the gas outlet of the proportional solenoid valve 201, and the electronic amplification and reference circuit module 204 is used, and then the analog-to-digital conversion module 206 converts the analog signal into a digital signal and sends it to the single-chip control module 207;

[0039] Finally, the actual sampling value of the carrier gas pressure and the input carrier gas pressure setting value are compared through the single-chip control module 207 to perform PID control, and the control voltage signal is sent to the digital-to-analog conversion module 205 for digital-to-analog conversion. The analog signal of the control voltage is then used to adjust the opening of the outlet of the proportional solenoid valve 201 through the integrated power drive circuit module 203, thereby maintaining the carrier gas output by the stabilized pressure gas source 4 to have a stable pressure output value.

[0040] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A gas chromatograph carrier gas pressure control system, characterized in that: include: A computer module (1), a pressure control unit (2), a power supply device (3) and a pressure-stabilized gas source (4); The stabilized pressure gas source (4) is used to store and output carrier gas, and input the carrier gas into the gas chromatograph through the pressure control unit (2); The pressure control unit (2) is electrically connected to the computer module (1), and the pressure of the carrier gas input into the gas chromatograph is controlled and adjusted through the computer module (1) and the pressure control unit (2); The power supply device (3) is electrically connected to the pressure control unit (2) and is used to supply power to the pressure control unit (2).

2. The gas chromatograph carrier gas pressure control system according to claim 1, characterized in that: The pressure control unit (2) comprises: a proportional solenoid valve (201), a pressure sensor (202), an integrated power drive circuit module (203), an electronic amplification and reference circuit module (204), a digital-to-analog conversion module (205), an analog-to-digital conversion module (206), a single-chip control module (207), and a microprocessor (208); The air inlet of the proportional solenoid valve (201) is connected to the pressure-stabilizing air source (4), and the air outlet of the proportional solenoid valve (201) is provided with a pressure sensor (202); The output signal of the pressure sensor (202) is electrically connected to a single-chip control module (207) via an electronic amplification and reference circuit module (204) and an analog-to-digital conversion module (206); The control end of the proportional solenoid valve (201) is electrically connected to a single-chip control module (207) via an integrated power drive circuit module (203) and a digital-to-analog conversion module (205); The single chip control module (207) is electrically connected to the microprocessor (208); The microprocessor (208) is electrically connected to the computer module (1).

3. A control method using the gas chromatograph carrier gas pressure control system according to claim 1, characterized in that: The following steps are involved: First, a carrier gas pressure setting value is input into the computer module (1), and sent to the single chip control module (207) through the microprocessor (208); Then, the pressure sensor (202) collects the sampling signal of the carrier gas pressure value discharged from the pressure-stabilized gas source (4) through the gas outlet of the proportional solenoid valve (201) through the electronic amplification and reference circuit module (204), and then converts the analog signal into a digital signal through the analog-to-digital conversion module (206), and sends it to the single-chip control module (207); Finally, the actual sampled value of the carrier gas pressure is compared with the input carrier gas pressure setting value through the single-chip control module (207), PID control is performed, and the control voltage signal is sent to the digital-to-analog conversion module (205) for digital-to-analog conversion. The converted analog signal is used to adjust the opening of the gas outlet of the proportional solenoid valve (201) through the integrated power drive circuit module (203), thereby maintaining the carrier gas output by the stabilized pressure gas source (4) with a stable pressure output value.

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